Embodiments relate generally to de-soldering tools, and in particular to a de-soldering tool for removing components from thermally dissipative printed wire boards.
Thermally dissipative printed wire boards (PWBs) are often employed on electronic devices to rid the product of undesired thermal energy (heat) generated during operation. Occasionally, the manufacturing process of such a PWB mandates the removal of a multi-pin, plated-through-hole (PTH) connector, previously soldered in place. Removing a multi-pin connector from this type of PWB with present de-soldering techniques however, presents great difficulty due to the thermally dissipative nature of the PWB and the thermal energy required to melt solder.
Specifically, the mechanics of these difficulties are manifested by several challenges. One challenge is the generation of sufficient heat to return the solder to a liquid state in light of the thermally dissipative nature of the PWB. Typically, the heat required to bring a solder junction to the melting point of solder requires the tool (“soldering iron”) to physically contact the junction for some time. This thermal rise time is greatly increased (if not halted entirely) by the thermally dissipative nature of the PWB.
Another challenge is the generation of sufficient heat to return the solder to a liquid state on the connector pins without causing undesired heating to other local components. Some de-soldering tools employ a directed flow of heated gas in an effort to establish the required heat on the connector pins. However, in some applications, there are much smaller surface mount technology (SMT) components located nearby that experience rapid heating, and by the force of the gas these components become dislodged, damaged or become removed altogether.
Another challenge is avoiding damage to other components on the PWB which possess much more restrictive thermal exposure specifications. Some de-soldering procedures employ a pre-heating cycle, which may damage other components or materials already soldered to the PCB. In some cases, these components do not have tolerance for the temperature ranges used in this pre-heating cycle. Examples of these materials or components may include capacitors, semiconductor devices, epoxies, adhesives, transformers, measurement probes, display components, tapes, labels, etc.
If the application of localized heating is excessive, the materials comprising the PWB may also incur damage. Thermal damage to the PWB is one criteria for rejection of manufactured boards under the IPC/EIA J-STD-001 manufacturing standards.
Uniform mechanical motion is needed along the entire length of larger connectors once the solder has entered a liquid state. Without applying a uniform lifting force simultaneously with the liquification of the solder, the connector's leads may generate a torque internal to the PWB during the extraction process potentially compromising the PWB structure.
Thus, there is a need in the art for a de-soldering tool that focuses thermal energy on solder connections and applies a uniform lifting force to remove components.